Question

The velocity of sound in oxygen at NTP is $v$. The velocity of sound in hydrogen at NTP will be

• A. $2\sqrt{2}v$
• B. $2v$
• C. $4v$
• D. none of these

Answer 1

Answer: (C)

$4v$

$v\propto \frac{1}{\sqrt{M_{gas}}}$

Here, v is the velocity of sound in the medium, $M_{gas}$ is the molecular weight of the gas.

Therefore,

$\frac{v_{H_2}}{v_{O_2}}=\sqrt{\frac{M_{O_2}}{M_{H_2}}}=\sqrt{\frac{32}{2}}=\sqrt{16}=4$

Option "C" is correct.